It keeps my brain juices flowing very nicely, man! I request more of this! A trilogy AT LEAST!

The only real problem I've noticed in this is the fact that the maps in which the minimum amount of color is all four colors, I kept spending hours trying to solve them with only three, when I find out I was trying the impossible, with no warning of this. I can see three solutions for this, either you leave a warning stating the "par" number of colors for each map, or you leave a warning saying which maps use ALL the colors, or you add one extra color in the game, which is only there to never be used on gold-star runs (but this is stupid and would make the game too easy for non-gold star guys.)